轴承腔润滑油沉积特征分析  

Analysis of oil deposition characteristic in an aero-engine bearing chamber

作　　者：李炎军[1] 陈薄[2] 张朝阳[1] 

机构地区：[1]中国燃气涡轮研究院,成都610500 [2]西南科技大学制造科学与工程学院,四川绵阳621010

出　　处：《燃气涡轮试验与研究》2015年第6期14-20,共7页Gas Turbine Experiment and Research

基　　金：国家自然科学基金(51475395)

摘　　要：通过对油滴变形和运动、油滴/腔壁碰撞过程质量和动量转移,以及二次油滴沉积的分析,在考虑油滴尺寸统计分布特征的情况下,建立了轴承腔中润滑油滴沉积过程中沉积质量和动量转移分析模型。探讨了油滴的变形特征和变形对油滴运行轨迹的影响,以及油滴变形和二次沉积效应对典型尺寸油滴沉积特性与润滑油滴沉积特性的影响。计算结果表明,由于变形后油滴所受阻力增加,运行轨迹更加弯曲;受气相介质影响,油滴无量纲长半轴和短半轴呈动态变化且变形量呈对称分布;一次沉积质量增加,一次动量转移减小;二次油滴沉积是润滑油沉积质量和动量转移的主要部分;相较于转子转速,密封进气量对油滴沉积质量的影响更大;动量转移量随着转子转速的升高而增大,而密封进气量的影响与之相反。Through the analysis of droplet deformation and motion, droplet/wall impingement and then the mass and momentum transfers in the process of deposition of droplets, and the secondary droplet deposition, the deposition mass and momentum transfer model was established with sufficient consideration of oil droplet diameter distribution in an aero-engine bearing chamber. The deformation characteristic and the effect of deformation on its trajectory were analyzed, and the effect of deformation and secondary deposition on typical diameter droplet deposition property and oil deposit.ion property were discussed. The calculation results show preliminary droplet trajectories become more bend due to deformation effect. The change of dimension- less major and minor semi-axis for deformation droplet is dynamic, and the deformation curves of random droplet between major and minor semi-axis are symmetric. When taking no account of secondary oil droplet deposition, the deposition mass of deformation droplets increases and the momentum transfer decreases in relative to those of spherical droplets. The total deposition mass and momentum transfer are mainly obtained from the secondary deposition. Compared with shaft speed, the deposition mass of lubrication are more influenced by air mass rate in the bearing chamber. The momentum transfer increases with increasing shaft speed and decreasing air mass rate.

关 键 词：航空发动机 滑油系统 轴承腔 油滴变形 二次油滴 沉积质量 动量转移 

分 类 号：V233.4[航空宇航科学与技术—航空宇航推进理论与工程]